database-query-optimization

database-query-optimization is a skill for Claude Code, Codex from aj-geddes/useful-ai-prompts. It costs 27 tokens per session (462 once invoked), scanned A, original, MIT.

A set of techniques for making database queries run faster, mainly through better SQL, indexes, and execution-plan analysis. An execution plan shows the steps the database uses to produce a result.

In plain words
What is it for?
It helps inspect query plans, choose indexes, improve joins and filters, and investigate rising database CPU use.
Why use it?
It reduces slow responses and unnecessary database work, especially when tables or query traffic become larger.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit It helps inspect query plans, choose indexes, improve joins and filters, and investigate rising database CPU use.

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Install with agentmods
npx agentmods add skills/aj-geddes/useful-ai-prompts/database-query-optimization
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add aj-geddes/useful-ai-prompts --skill database-query-optimization
Clone the repo
git clone --depth 1 https://github.com/aj-geddes/useful-ai-prompts

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for database-query-optimization

README.md
[![agentmods](https://agentmods.dev/badge/skills/aj-geddes/useful-ai-prompts/database-query-optimization/github.svg)](https://agentmods.dev/skills/aj-geddes/useful-ai-prompts/database-query-optimization)
Your own site
<a href="https://agentmods.dev/skills/aj-geddes/useful-ai-prompts/database-query-optimization"><img src="https://agentmods.dev/badge/skills/aj-geddes/useful-ai-prompts/database-query-optimization/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for database-query-optimization

Your own site · 80×15
<a href="https://agentmods.dev/skills/aj-geddes/useful-ai-prompts/database-query-optimization"><img src="https://agentmods.dev/badge/skills/aj-geddes/useful-ai-prompts/database-query-optimization.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 27 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 462 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • Socket pass 18 Mar 2026
  • Snyk pass 4 Mar 2026
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00027 $0.00462
Opus 5 $0.00014 $0.00231
Sonnet 5 $0.00005 $0.00092
Haiku 4.5 $0.00003 $0.00046

Measured 9d ago against content hash 84602ad1031f, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

database-query-optimization scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 9d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/validate-schema.sh), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/database-query-optimization/SKILL.md · 82 lines

What it actually says

Database Query Optimization

Table of Contents

Overview

Slow database queries are a common performance bottleneck. Optimization through indexing, efficient queries, and caching dramatically improves application performance.

When to Use

  • Slow response times
  • High database CPU usage
  • Performance regression
  • New feature deployment
  • Regular maintenance

Quick Start

Minimal working example:

-- Analyze query performance

EXPLAIN ANALYZE
SELECT users.id, users.name, COUNT(orders.id) as order_count
FROM users
LEFT JOIN orders ON users.id = orders.user_id
WHERE users.created_at > '2024-01-01'
GROUP BY users.id, users.name
ORDER BY order_count DESC;

-- Results show:
-- - Seq Scan (slow) vs Index Scan (fast)
-- - Rows: actual vs planned (high variance = bad)
-- - Execution time (milliseconds)

-- Key metrics:
-- - Sequential Scan: Full table read (slow)
-- - Index Scan: Uses index (fast)
-- - Nested Loop: Joins with loops
-- - Sort: In-memory or disk sort

Reference Guides

Detailed implementations in the references/ directory:

Guide Contents
Query Analysis Query Analysis
Indexing Strategy Indexing Strategy
Query Optimization Techniques Query Optimization Techniques
Optimization Checklist Optimization Checklist

Best Practices

✅ DO

  • Follow established patterns and conventions
  • Write clean, maintainable code
  • Add appropriate documentation
  • Test thoroughly before deploying

❌ DON'T

  • Skip testing or validation
  • Ignore error handling
  • Hard-code configuration values
Files

What ships with it

6 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 9d ago First seen · 82 lines · 27 tokens per session scan A 84602ad1031f

Subscribe to this mod's changes

database-query-optimization is a skill published in the GitHub repository aj-geddes/useful-ai-prompts (338 stars, last pushed 6mo ago), licensed MIT. It adds 27 tokens to every session and 462 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.

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